Now the aId value of the mergedEntity is null. In the previous 1.0.1
release the primitive attributes were copied.

I looked at the source code of the ObjectBuilder.mergeIntoObject(Object
target, boolean isUnInitialized, Object source, MergeManager mergeManager,
boolean cascadeOnly, boolean isTargetCloneOfOriginal) method, that is part
of the merge logic.

The source code looks a bit strange, because the isTargetCloneOfOriginal
will doesn't take any effect. I think there is a problem in the boolean
logic.

For me the second "else if" doesn't make sense, because it will never be
reached. The same expression is in the first if statement, so this will be
executed first. Perhaps there was forgotten to negate the
isTargetCloneOfOriginal Boolean in the second if statement ?

I have attempted to reproduce this error and I can not. We also have
tests in our Regression testing that tests this functionality and continue
to pass. Are you sure that you are looking at the managed object? Are
you sure you are merging the object that you expect to be merging? Can
you provide a simple testcase?

The method you referenced to does seem to have a simple error. The else
if should be removed.
--Gordon